No answer means nobody currently browsing knows.? You could try the aframe groups on Facebook and see if they have any answers.? Someone there might know.? But if you're looking for a part that rarely breaks, people on the forums are just not going to know what the replacement is.? In that case Aliner is your best bet.? They may be slow but they will answer eventually if you bug them.

The FB groups to ask are "Aframe Campers: Aliner, Chalet, ..." and "Chalet Camping (Chalet, Aliner, ..."